Remove dependency on forms (#596)

* Remove forms dependency

* Also remove dependency from mix.lock

Co-authored-by: Awlex <no thank you>

Author: Awlexus

apps/language_server/lib/language_server/dialyzer/utils.ex

@@ -49,22 +49,29 @@ defmodule ElixirLS.LanguageServer.Dialyzer.Utils do
 
   defp module_references(mod) do
     try do
-      forms = :forms.read(mod)
-
-      calls =
-        :forms.filter(
-          fn
-            {:call, _, {:remote, _, {:atom, _, _}, _}, _} -> true
-            _ -> false
-          end,
-          forms
-        )
-
-      for {:call, _, {:remote, _, {:atom, _, module}, _}, _} <- calls, uniq: true, do: module
+      for form <- read_forms(mod),
+          {:call, _, {:remote, _, {:atom, _, module}, _}, _} <- form,
+          uniq: true,
+          do: module
     rescue
       _ -> []
     catch
       _ -> []
     end
   end
+
+  # Read the Erlang abstract forms from the specified Module
+  # compiled using the -debug_info compile option
+  defp read_forms(module) do
+    case :beam_lib.chunks(:code.which(module), [:abstract_code]) do
+      {:ok, {^module, [{:abstract_code, {:raw_abstract_v1, forms}}]}} ->
+        forms
+
+      {:ok, {:no_debug_info, _}} ->
+        throw({:forms_not_found, module})
+
+      {:error, :beam_lib, {:file_error, _, :enoent}} ->
+        throw({:module_not_found, module})
+    end
+  end
 end

apps/language_server/mix.exs

@@ -28,7 +28,6 @@ defmodule ElixirLS.LanguageServer.Mixfile do
     [
       {:elixir_ls_utils, in_umbrella: true},
       {:elixir_sense, github: "elixir-lsp/elixir_sense"},
-      {:forms, "~> 0.0"},
       {:erl2ex, github: "dazuma/erl2ex"},
       {:dialyxir, "~> 1.0", runtime: false},
       {:jason_vendored, github: "elixir-lsp/jason", branch: "vendored"},

mix.lock

@@ -4,7 +4,6 @@
   "elixir_sense": {:git, "https://github.com/elixir-lsp/elixir_sense.git", "4a857f2c262b9f8ac2d72e31f4806cecc740192a", []},
   "erl2ex": {:git, "https://github.com/dazuma/erl2ex.git", "244c2d9ed5805ef4855a491d8616b8842fef7ca4", []},
   "erlex": {:hex, :erlex, "0.2.6", "c7987d15e899c7a2f34f5420d2a2ea0d659682c06ac607572df55a43753aa12e", [:mix], [], "hexpm", "2ed2e25711feb44d52b17d2780eabf998452f6efda104877a3881c2f8c0c0c75"},
-  "forms": {:hex, :forms, "0.0.1", "45f3b10b6f859f95f2c2c1a1de244d63855296d55ed8e93eb0dd116b3e86c4a6", [:rebar3], [], "hexpm", "530f63ed8ed5a171f744fc75bd69cb2e36496899d19dbef48101b4636b795868"},
   "getopt": {:hex, :getopt, "1.0.1", "c73a9fa687b217f2ff79f68a3b637711bb1936e712b521d8ce466b29cbf7808a", [:rebar3], [], "hexpm", "53e1ab83b9ceb65c9672d3e7a35b8092e9bdc9b3ee80721471a161c10c59959c"},
   "jason_vendored": {:git, "https://github.com/elixir-lsp/jason.git", "ee95ca80cd67b3a499a14f469536140935eb4483", [branch: "vendored"]},
   "mix_task_archive_deps": {:git, "https://github.com/JakeBecker/mix_task_archive_deps.git", "50301a4314e3cc1104f77a8208d5b66ee382970b", []},